Mechanical transfer of microorganisms on the external appendages of the vector and internalization of the agent by the vector, requiring subsequent regurgitation, defecation, or penetration of the skin or mucosal surface.

Transovarian and transtadial transmission.

Transmission by ingestion of contaminated water or food, medical instruments, or infusion of products such as blood.

Passage of a pathogenic agent through the air over long distances.